Clearly because you fundamentally misunderstand probability.
A solid seat is a 95% chance of winning or higher. A party will lose let's say 1 in 20 of these.
A likely seat is a 75% chance. A party will lose about 1 in 4 or 5 of these.
A leaning seat will be lost about 2 in 5 times.
Republicans by 538s count has 135 solid seats, 49 likely seats, and 13 leaning seats. They will win an average of 128, 37, and 8 if these if I'm being generous.
You are treating these 197 seats as 197 seats won. In reality they are closer to 173 seats won.
Take the toss ups and split them in half and you get 182 seats for Republicans not 200 something.
Do the same for Democrats now. 193 (!!!) solid seats, 17 likely seats, 10 leaning seats. Translates to 10+4+4=18 pick ups for a total of 200 seats AFTER toss ups are calculated. Not before.
You're fundamentally misunderstanding how many safe or safe leaning seats will be lost.
You are assuming probabilities are clear cut answers.
Go back to the 2014 midterms. How many solids and likelies and such actually flipped.
Okay bud.
Did 25% of likelies 5% of solids, 40% of leans flip? Was it even close to those numbers? ---